1. Field of the Invention
The present invention relates to a method of and an apparatus for applying a light-shield member to a photosensitive member, and more particularly to a method of and an apparatus for applying a light-shield member to a photosensitive member by delivering the light-shield member in a direction perpendicular to the photosensitive member, which is of the type to be loaded in a bright room, joining an end of the light-shield member to an end of the photosensitive member, and thereafter winding the light-shield member on an outermost layer of the photosensitive member.
2. Description of the Related Art
Some photosensitive products comprise a photosensitive member, which is of the type to be loaded into an exposure device in a bright room, and a light-shield member such as a light-shield film wound on an outermost layer of the photosensitive member.
For packaging a photosensitive member with a light-shield member, it has heretofore been customary to take out the light-shield member, cut off the light-shield member into predetermined dimensions, deliver and position the severed light-shield member with respect to the photosensitive member, cut off ends of the light-shield member and the photosensitive member, hold them in abutment against each other, and join the abutting ends to each other. In the packaging process, the light-shield member is supplied to the end of the photosensitive member in a longitudinal direction thereof. It is necessary to remove any debris cut off from the light-shield member and the photosensitive member. For carrying out the packaging process, therefore, various different technologies are required. For example, these various different technologies include, among others, (a) the delivering and positioning of the light-shield member, (b) the cutting off of the light-shield member into predetermined dimensions, (c) the joining of the light-shield member and the photosensitive member to each other, and (d) the processing of debris cut off from the light-shield member and the photosensitive member.
Conventional arrangements for performing (a) the delivering and positioning of the light-shield member are disclosed in Japanese laid-open patent publications Nos. 59-219198, 1-256459, and 5-338877. These publications disclose that a sheet-like member is delivered by a belt conveyor and stopped and positioned by pins and nip rollers. If the light-shield member is in the form of a web, typically a light-shield film whose surface a low coefficient of friction and which is of low rigidity, then it is difficult to deliver the web with a belt conveyor and stop and position the web with pins and nip rollers.
Japanese laid-open patent publication No. 9-43781 reveals a known technique for carrying out (b) the cutting off of the light-shield member into predetermined dimensions. Generally, it is known to prepare light-shield members of different widths for use with photosensitive members of different widths, in relation to the cutting off of the light-shield member into predetermined dimensions. The preparation of light-shield members of different widths is necessary because a light-shield member and a photosensitive member have to be of the same width in order to hold their ends in abutment against each other and join them to each other. For a given photosensitive member, therefore, a light-shield member whose width matches the width of the given photosensitive member needs to be selected from the prepared light-shield members and then to replace any existing light-shield member. If there are many available photosensitive members of different widths, then it is highly tedious and time-consuming to select a matching light-shield member and replace any existing light-shield member with the selected light-shield member. Furthermore, a material loss tends to be large due to debris produced when light-shield members are cut off.
Prior processes for abutting and joining ends of a light-shield member and a photosensitive member to each other, in connection with the above process (c), are known from Japanese laid-open patent publications Nos. 54-91676 and 60-48858. According to the known processes, an end of a light-shield member having a predetermined width is positioned in abutment against an end of a photosensitive member, and then the abutting ends are joined to each other. However, these processes are disadvantageous in that when the light-shield member and the photosensitive member are delivered to a joining mechanism, they are liable to be displaced out of a desired joining position and cannot well be joined to each other.
FIGS. 15 through 17 of the accompanying drawings show unwanted joined states resulting from the above processes. FIG. 15 illustrates the manner in which a light-shield member xe2x80x9caxe2x80x9d supplied from its blank roll is positioned obliquely with respect to a photosensitive member xe2x80x9cbxe2x80x9d and joined to the photosensitive member xe2x80x9cbxe2x80x9d by a joining tape xe2x80x9ccxe2x80x9d. FIG. 16 illustrates the manner in which a light-shield member xe2x80x9caxe2x80x9d is transversely displaced out of alignment with a photosensitive member xe2x80x9cbxe2x80x9d due to poor positioning accuracy, and joined to the photosensitive member xe2x80x9cbxe2x80x9d by a joining tape xe2x80x9ccxe2x80x9d. FIG. 17 illustrates the manner in which a light-shield member xe2x80x9caxe2x80x9d that is narrower than a photosensitive member xe2x80x9cbxe2x80x9d is joined to the photosensitive member xe2x80x9cbxe2x80x9d by a joining tape xe2x80x9ccxe2x80x9d.
The joined states shown in FIGS. 15 through 17 may happen at the same time to cause a combined joining failure. Any of the undesired joined states shown in FIGS. 15 through 17 should be avoided because they will impair the light shielding capability for the photosensitive member xe2x80x9cbxe2x80x9d.
As the process of carrying out (d) the processing of debris cut off from the light-shield member and the photosensitive member, a process of automatically discharging debris using a belt conveyor or an air chute is disclosed in Japanese laid-open patent publication No. 7-266291. The disclosed process is effective in discharging debris produced from highly rigid corrugated board or small-size punched debris. However, this process is not suitable for processing less rigid debris from a light-shield film, for example, and pieces of debris having different sizes, and fails to discharge debris from below members that are joined to each other.
It is a general object of the present invention to provide a method of and an apparatus for applying a light-shield member to a photosensitive member which has switched from another photosensitive member of a different width, by cutting off the light-shield member to a width that matches the width of the photosensitive member and joining the severed light-shield member to the photosensitive member, without having to prepare in advance another light-shield member whose length matches the width of the photosensitive member, so that high productivity and labor-saving capability can be achieved.
A major object of the present invention is to provide a method of and an apparatus for applying a light-shield member to a photosensitive member by smoothly delivering the light-shield member, accurately stopping and positioning the light-shield member, and reducing a material loss due to debris cut off from the light-shield member when the light-shield member and the photosensitive member are joined to each other.
According to the present invention, a first feeding mechanism feeds an elongate light-shield member in a direction transverse to a longitudinal direction of a rolled photosensitive member, and then a first cutting mechanism cuts off a leading end portion of the elongate light-shield member into a light-shield member having a predetermined shape corresponding to the width of the rolled photosensitive member. Thereafter, a second feeding mechanism feeds the light-shield member to an overlapping position and causes a transverse end of the light-shield member to overlap a longitudinal end of the rolled photosensitive member. In the overlapping position, a joining mechanism joins the light-shield member endwise to the rolled photosensitive member. Finally, an applying mechanism winds the light-shield member around the rolled photosensitive member thereby to apply the light-shield member to an outer circumferential surface of the rolled photosensitive member.
Even when the photosensitive member is changed to a new photosensitive member having a different width, the length of the light-shield member can be adjusted to the width of the new photosensitive member. Since the light-shield member of fixed width can be used with all available photosensitive member having different widths, it is not necessary to replace the light-shield member.
It is preferable to further provide a second cutting mechanism for cutting off the overlapping ends of the light-shield member and the rolled photosensitive member, and a debris discharging mechanism for automatically discharging debris produced by the second cutting mechanism.
According to the present invention, furthermore, the first cutting mechanism comprises a pair of cutter blades. Preferably, the cutter blades comprise fixed blades, and the first cutting mechanism has pressing means for pressing the elongate light-shield member against the fixed blades. Preferably, the pressing means comprises a pair of presser rollers, and the first cutting mechanism further comprises a suction box for attracting the elongate light-shield member, and a holder frame for holding the elongate light-shield member against the fixed blades.
With the above arrangement, it is possible to simultaneously cut a trailing end of the light-shield member and a leading end of the elongate light-shield member in a single cutting cycle. Since the elongate light-shield member is cut when it is pressed against the fixed blades by the holder frame, the elongate light-shield member can be cut with highly dimensional accuracy without sagging or being positionally displaced. If sides of the fixed blades are surrounded by resilient members, then when the elongate light-shield member is pressed by the presser rollers, the resilient members are compressed, allowing the elongate light-shield member to contact the fixed blades and be cut thereby. After the cutting of the elongate light-shield member, the presser rollers are elevated, and the resilient members are expanded back to surround the fixed blades. Therefore, the light-shield member is not cut or otherwise damaged by the fixed blades when the light-shield member is subsequently fed.
The first feeding mechanism comprises length varying means for varying the length of the light-shield member. Therefore, the length of the light-shield member can simply and accurately be adjusted to match the width of the rolled photosensitive member which may be changed.
Moreover, the first feeding mechanism comprises a suction drum and first suction belts. The rotational speed of the suction drum is controlled by a rotational speed control means. The suction drum is controlled by the rotational speed control means to withdraw a length of the light-shield member which matches the width of the rolled photosensitive member. The first suction belts held in rolling contact with the suction drum should preferably driven in synchronism with the suction drum.
The second feeding mechanism preferably feeds the light-shield member for a length corresponding to the width of the rolled photosensitive member while attracting the light-shield member.
The length of the elongate light-shield member can thus be fed and cut off accurately, and positioned easily in the overlapping position.
According to the present invention, furthermore, a second cutting mechanism cuts off the overlapping ends of the light-shield member and the rolled photosensitive member. Abutting ends of the light-shield member and the rolled photosensitive member, which are produced by the second cutting mechanism, are joined by the joining mechanism. The light-shield member and the rolled photosensitive member can be joined at their abutting ends, rather than overlapping ends or spaced ends.
In this manner, the transverse end of the light-shield member and the longitudinal end of the rolled photosensitive member, which are held in the overlapping position, can be cut off in one cutting cycle and joined to each other.
Preferably, the second cutting mechanism comprises a plurality of suction boxes for attracting the ends of the light-shield member and the rolled photosensitive member in position, and an upper rotary blade and a lower blade for cutting off the overlapping ends of the light-shield member and the rolled photosensitive member in coaction with each other thereby to produce the abutting ends of the light-shield member and the rolled photosensitive member, the lower blade being disposed between the suction boxes. The joining mechanism comprises means for joining the abutting ends while attracting the light-shield member and the rolled photosensitive member.
The second cutting mechanism comprises a pair of guide rollers disposed one on each side of the upper rotary blade for pressing the upper rotary blade, and side pressure adjusting means for adjusting a side pressure of the upper rotary blade. The upper rotary blade is displaced by a ball screw or the like in a direction to cut off the overlapping ends. The light-shield member and the photosensitive member can thus be cut off with high dimensional accuracy without flexing and being positionally displaced.
Debris cut off the light-shield member when the overlapping ends of the light-shield member and the photosensitive member are cut off is automatically discharged by the debris discharging mechanism. The debris drops below the joined ends of the light-shield member and the photosensitive member, and hence can be discharged highly efficiently unlike the conventional arrangement in which it is difficult to discharge such debris.
The debris discharging mechanism comprises a suction box for attracting the debris, a chuck mechanism for holding the debris, and a stock tray for storing the debris. The debris discharging mechanism thus constructed is capable of efficiently and automatically discharging debris that is present beneath the joined ends of the light-shield member and the photosensitive member.
The above and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which preferred embodiments of the present invention are shown by way of illustrative example.